This invention relates generally to holders for receiving contact lenses, and more particularly to indicating means to be employed with holders to provide the user with an indication that the sterilizing temperature has been reached.
Contact lenses, both of the hard and soft type, often must be sterilized before they are suitable for use. The large numbers of different lens prescription often encountered by doctors and manufacturers require that the individual pairs of contact lenses be maintained separate. To this end, each pair of contact lenses is inserted into a separate container which may also have receptacles therein for holding the right and left lens spaced apart so they do not become confused. These containers are commonly referred to as contact lens holders. A quantity of fluid is then administered to the container and then the container is placed in an autoclave or boiler for heating the fluid to a sterilization temperature. The fluid within the container is in direct contact with the lenses and effects sterilization thereof. After the sterilization temperature has been reached, the contact lens holders are removed from the heating apparatus and allowed to cool sufficiently to enable removal of the contact lenses. One common type of contact lens holder which is used for the sterilization of contact lenses is shown in U.S. Pat. No. 3,770,113. One problem presently encountered with this and other types of holders is that it is virtually impossible to determine whether or not the lens have been heated sufficiently to reach the sterilization temperature. Should the heating apparatus malfunction, or the heating cycle be of insufficient duration to raise the temperature of the fluid within the holder to the desired sterilization temperature, there will be no sterilization of the contact lenses. This condition can go undetected and therefore may cause irritation or infection to the user of the unsterilized contact lenses.
The present invention, as will be explained more fully hereinafter, is concerned with overcoming the problem inherent in the prior art. More specifically, the present invention provides means which will indicate to a user whether or not the proper sterilization temperature was in fact reached.